So that everyone can see the article, links to an index page, and the specific newsletter: http://www.nist.gov/pml/wmd/pubs/wmd-newsletter-archive.cfm http://www.nist.gov/pml/wmd/pubs/upload/WMConnection-Vol4-Issue5-Sept-11-2013.pdf Yes, the author confuses units and values at several points. However, the examples are correct in that they determine the larger value for comparison to actual net contents. If we believe metric-only (permissive or otherwise) will come to pass, then I have a second concern. The article suggests ambivalence in whether to convert customary to metric or metric to customary to determine the larger value. It also suggests the inspector should work in the native units of the larger claim. This leads to the inspector working in both customary and metric according to which claim is larger. Would it not be better to ALWAYS convert customary to metric, then compare actual net contents to the larger metric value? Learning to do this now would help inspectors prepare for a metric only future, and the process would be simplified when we become metric only. I am concerned an inspector may become used to always converting the metric claim to customary and working in customary. This will leave him ill-prepared for a metric future. He should have the equipment and necessary training to do the comparison with actual in metric.
________________________________ From: "mechtly, eugene a" <mech...@illinois.edu> To: U.S. Metric Association <usma@colostate.edu> Cc: U.S. Metric Accociation <usma@colostate.edu>; "mechtly, eugene a" <mech...@illinois.edu> Sent: Saturday, September 14, 2013 9:44 PM Subject: [USMA:53253] FW: W&M Connection Vol. 4 Issue 5 Checking net contents is *not* a determination of which "unit" is larger, but is a confirmation of the validity of the larger *value* (number and unit) declared on the label of a container bearing dual declarations (or measured by the inspector). Eugene Mechtly ________________________________________ From: mechtly, eugene a Sent: Friday, September 13, 2013 4:00 PM To: david.sef...@nist.gov; U.S. Metric Accociation Cc: mechtly, eugene a Subject: W&M Connection Vol. 4 Issue 5 David, I just read your article of September 11th. Unfortunately, the FPLA has still not been amended to *permit* metric-only labeling on products regulated at the Federal Level although metric-only labels are now permitted on most products regulated at state level by *nearly all* states of the USA! Given the FPLA as is continues to exist in US Law, you had no choice but to discuss "duality"; SI Units and Units Outside the SI. There is one technical point what I would have recommended. Compare the "values* of both declarations; a number and a unit in SI with the equivalent of the other number and its non-SI unit, *afer* the latter has been converted to its value, i.e. its number and unit in SI. The larger of the two "values" of the declarations (or two measurements) are to be compared, not the larger of the two units in question. Eugene Mechtly
